基于模糊-内模双环控制的船岸并网系统

针对靠港船舶与岸电装置并网失电、并网电压跌落、频率不稳定以及并网环路电流大等问题,提出了一种基于下垂原理的外环模糊控制与内环内模控制相结合的逆变器的船岸并网系统,实现靠港船舶与岸电的柔性并网,即并网冲击可控、负载平稳转移,保证负荷不断电情况下实现平滑切换。对船岸并网系统整体过程进行设计与仿真：整流侧使用三相PWM闭环控制；逆变环节采用基于下垂原理的模糊PI电压外环、内模电容电流内环的双环控制结构；船舶供电系统采用同步发电机模型。仿真结果表明：直流侧电压输出稳定并可调,高低压上船方式可调范围分别为500~1000V、1200~2000V；并网电流谐波含量分别为0.35%、0.40%；并网电压幅值、频率稳定且实现负荷平稳转移。

A Shore-to-ship Grid-connected Power Supply System Based on Fuzzy-logic and Internal Model Control

In this paper, in order to solve the problems of power outage, voltage drop, frequency instability and high current in the grid connection loop, a shore-to-ship grid-connected system based on theSdroopScontrol with the combination of fuzzy control and internal model control is proposed. By adopting the proposed control strategy, the flexible grid-connection between shore power and cruise ship can be realized, which means the grid-connection impact is controllable, the load transfer being stable and smooth. The complete process of shore to ship grid-connected system was designed and simulated. The rectifier used three-phase PWM technology; Based on droop principle, the inverter adopted the double loop control structure which consists of fuzzy PI for voltage loop and internal model control (IMC) for capacitor current loop. The power system in the cruise ship adopted synchronous generator model. Simulation results showed that the output voltage of the dc link is stable and adjustable. The adjustable range of the high-voltage and low-voltage embarkation mode is 500~1000V and 1200~2000V, respectively. The harmonic content of the grid-connected current is 0.35% and 0.40%, respectively. The voltage amplitude and frequency are stable and the load can be transferred smoothly from ship to shore.